When Mia accuses Ben of ripping her favorite pair of jeans, she drags him to the store, where he has to break the tough news to Mia... it's time for pregnancy pants. Meanwhile Joel decides to get himself into shape after he finds out he's ranked last in Vicky and her girlfriends' fantasy husband draft website, and Maddie goes to extreme lengths to impress Casey with her high regard for the U.S. Postal Service.

Casey has big plans for his first Valentine's Day with Mia. But Ben and Joel tell him that their rule is to never buy expensive Valentine's Day gifts for their ladies because doing so would set a costly precedent. Casey goes ahead with his plans anyway, and Ben realizes that he too wants to show Maddie how he feels. When Joel finds out, he decides to compete with them no matter the cost - and gets singer/pianist Michael Feinstein to perform.

Ben hopes to get his name inscribed on a shamrock at his favorite bar, but it looks like he will strike out in his efforts when he learns the establishment's owner is New York Yankee Nick Swisher (appearing as himself), with whom Ben has a bad history. Meanwhile, Mia and Maddie use a secret language to convey their apprehension about attending a charity event with Vicky.

Joel tries to use his bargaining skills to get Mia the baby stroller of her dreams; Maddie worries she's losing her passion to be a lawyer.